My friends 92 f150 won't start.He has changed the fuel filter .When he turns the key on the fuel pumps run but do not shut off.Same on both tanks.What could the problem be?It quit while driving but he was able to get it restarted and get it home but now it won't start.

 

Fuel pump isnt supposed to turn off. Have him ck for spark. Get back 2 us.

 

I thought I read somewhere that with the ignition switch on that the pumps would run for 5 seconds and would turn off.Thats not in the start position but in the on position.I might be wrong though.

 

this is a classic sign of a bad computer.

 

Agreed with QL.

The pumps should prime for 1 second and then shut off. When they don't, it very often means the computer is kaput.

Boneyard is the best place for a replacement. Make sure to get one from the same engine/trans combo, same year would also be nice.

 

to remove computer:

disconnect batt

computer i located in engine compartment below and to the outside of brake master cyl.

unbolt the harness unbolt the comp.

unbolt the back of the plastic inner fender.

pull out computer.

go to junkyard.

reverse order.

drink massive amount of beer, you just saved your friend a ton of time and money.

good luck!